Read 1973-76, for young readers, pictures every page, text every page?, fields of pumpkins between their homes. I think the girl was the pumpkin princess and the boy was a commoner or vice versa. Does he invent pumpkin pie? They both love the pie or pumpkin so much that they eat until they are each as round as pumpkins. Story ends with them literally rolling away in their happy roundness, likely disobeying parents through their connection.